smg

player sh
  [planA], [planA_Dev], [planB], [planB_Dev]
endplayer

player learned_controller
  controller, env
endplayer

global move : [0..2] init 0;

const int lengthA = 10;
const int lengthB = lengthA + 5;

global stepA : [0..lengthA] init 0;
global stepB : [0..lengthB] init 0;

global planA : bool init true;
global shieldPlanA : bool init true;

global stepTaken : bool init false;
global waiting : bool init false;

const int waiting_cost = 2;

const double blockedProb = 0.5;
module controller
  [] move=0 & shieldPlanA & stepA<lengthA -> (planA'=true)  & (stepTaken'=false) & (waiting'=false) & (move'=1);
  [] move=0 & shieldPlanA & stepA<lengthA -> (planA'=false) & (stepTaken'=false) & (waiting'=false) & (move'=1);

  [] move=0 & !shieldPlanA & stepB<lengthB -> (planA'=false) & (stepTaken'=false) & (waiting'=false) & (move'=1);
endmodule

module shield
  [planA] move=1 & planA ->  (shieldPlanA'=true)  & (move'=2);
  [planB_Dev] move=1 & planA ->  (shieldPlanA'=false) & (move'=2);

  [planB] move=1 & !planA -> (shieldPlanA'=false) & (move'=2);
  [planA_Dev] move=1 & !planA -> (shieldPlanA'=true)  & (move'=2);
endmodule

module env
  [] move=2 & shieldPlanA& stepA<lengthA -> 1 - blockedProb : (stepA'=min(stepA+1, lengthA)) & (stepTaken'=true) & (move'=0) + blockedProb : (stepA'=stepA) & (waiting'=true) & (move'=0);

  [] move=2 & !shieldPlanA & stepB<lengthB -> (stepB'=min(stepB+1, lengthB)) & (stepTaken'=true) & (move'=0);

  [] move=2 & (lengthB=stepB | lengthA=stepA) -> (stepTaken'=false) & (waiting'=false);
endmodule

rewards "travel_costs"
  stepTaken : 1;
  waiting : waiting_cost;
endrewards